1. Field of the Invention
This invention relates to road vehicles, particularly to road vehicles having load-restraining mechanisms.
2. Prior Art
Vacuum restraint systems are known in which a sheet of flexible impermeable material is put over a load on an air-impermeable base and in which the periphery of the sheet is then sealed to the base by an airtight seal. The space within the sheet is then partially evacuated; the reduced pressure holds the sheet tightly down onto the load so holding the load firmly on the base. Such systems find particular application for loads which may have to be stored for long periods and may have to be transported. It is usual therefore to use a separate pallet as the base. It has been proposed that a vacuum restraint system should be used for holding a load on a vehicle but the work involved in making the airtight seal, e.g. by tucking the whole periphery of the sheet into a groove formed in the base and then inflating a tube, on the peripheral edge of the sheet, to hold the sheet tightly in the groove, is uneconomic if the goods are to be on the vehicle only for a short time.